ST. LOUIS (AP) — St. Louis’ police chief says he’s confident the city prosecutor’s decision not to charge two officers in last year’s shooting death of a black 18-year-old was the result of a “comprehensive review.”

Police Chief Sam Dotson said his department plans its own review over possible tactical lessons that could be learned from Mansur Ball-Bey’s August 2015 death.

Circuit Attorney Jennifer Joyce concluded no evidence disproves police claims of self-defense in Ball-Bey’s death.

Joyce said the officers and a witness reported seeing an armed Ball-Bey run from a home during a raid, and the officers said they fired at him after he pointed his gun toward one of them.

An attorney for Ball-Bey’s family has questioned the police account that Ball-Bey was armed.